Project Tampa Bay
The Fish and Wildlife Research Institute (FWRI), in partnership with Mote Marine Laboratory, completed a large-scale redfish (red drum) stock enhancement research project in Tampa Bay. The goal of this project was to determine if stocking hatchery fish can increase the number of fish caught by anglers in Tampa Bay and to experimentally determine the best sizes and locations for stocking to meet that goal in the most cost-effective manner.
FWRI scientists began raising redfish for Project Tampa Bay in August 1999. Stocking began in the spring of 2000 and continued until December 2004. Approximately 4 million juvenile red drum were released during this time. Because the goal of this program was to increase the number of redfish caught by anglers, it was important to stock fish where many people already fish for them. Anglers helped track these fish by reporting capture information on any redfish caught in Tampa Bay and by cooperating with scientists conducting creel surveys.
Before this project began, an in-depth process was designed and implemented by scientists to identify and prioritize potential candidate stock enhancement species and stocking location. The process included a survey of many saltwater fishing license holders, which identified redfish, common snook and sea trout as the top three species of angling interest. After a careful evaluation using a variety of criteria, scientists selected redfish as the species of choice for stocking Tampa Bay.
Tampa Bay was selected as the pilot stock enhancement site for several reasons. First, it already has an existing redfish fishery as well as an abundance of redfish nursery habitat. Secondly, the former FWC marine hatchery, called the Stock Enhancement Research Facility (SERF), was located near the shore of Tampa Bay in northwest Manatee County and had been culturing redfish since it opened in April 1988. Third and most importantly, the FWRI Fisheries Independent Monitoring (FIM) program had been monitoring wild fish populations in Tampa Bay and many of its contributing river systems since late 1980’s, therefore providing scientists valuable pre and post stocking data.
The Alafia River was the primary study area, and the Little Manatee River was a secondary release area for this project. These rivers were selected because most juvenile redfish documented in Tampa Bay by FIM were captured within these two river systems. FIM’s monitoring efforts provided data on the abundance of wild redfish in these locations before and after hatchery fish were introduced. More importantly, the monitoring identified hatchery fish in the wild and this allowed for survival estimates to be determined as well as contribution to the overall fishery.
Red drum were grown in ponds at SERF (Palmetto, FL) from eggs to one of three size groups, called phases. Phase 1 fish were up to 1.5 inches and are consistent with wild fish size during October through December. Phase 2 fish were 2-4 inches and are consistent with wild fish in January through April. Phase 3 fish were 6-9 inches and were the same size as wild fish during May-August. Phase 1 and 2 fish were not large enough to mark with external tags, but were identified as a hatchery fish by their DNA “fingerprint” as a hatchery fish specific to the group, or breeding pairs, from which they were spawned. This allowed for suitability of the locations of release for each group of phase 1 and 2 to be assessed from fish captures by a genetic analysis. Phase 2 fish were also tagged with internal tags identifiable by FWC’s Fisheries Independent Monitoring Group. Phase 3 fish were marked with external tags and were reported by anglers to the FWC Fish Tag Hotline to assist scientists with gathering data.
Tringali, M.D., Leber, K.M., Halstead, W.G, McMichael, R., O’Hop, J., Winner, B., Cody, R., Young, C., Neidig, C., Wolfe, H., Forstchen, A., and Barbieri, L. 2008. Marine stock enhancement in Florida: A multi-disciplinary, stakeholder-supported, accountability – based approach. Reviews in Fisheries Science 16(1-3): 51-57.
Tringali 2006. A Bayesian approach for the genetic tracking of cultured and released individuals. Fisheries Research 77: 159-172.